Telemetry

Abstract

A remote telemetry metering system, includes one or more battery-powered metering units and a central data collection unit, each including a radio transceiver. The central data collection unit transmits a signal including power down time information and transmits instructions, which is received by each metering unit. Each metering unit extracts the power down time information and transmits instructions from the signal and, if appropriate, transmits data in response to the data transmit instructions; this data being collected by the central data collection unit. The metering units then interrupt the power supply to their transceivers for a period of time which is dependent upon the power down time information. The central data collection unit delays, for a slightly longer period of time before transmitting a further signal via its transceiver, at which time the power supply to the transceiver of each metering unit has already been resumed. By allowing the metering units to power down to a quiescent state under the control of the central data collection unit, flexibility is ensured and power consumption minimized.

I claim: 
     
       1. A data gathering unit comprising a transceiver for the communication of information between the data gathering unit and a central data collection unit, means for transmitting data in response to a signal received via the transceiver, means for extracting power down time information from the signal received via the transceiver and means for subsequently interrupting the power supply to the transceiver for a period of time dependent upon the power down time information. 
     
     
       2. A data gathering unit according to claim 1 in which the data gathering unit comprises a meter adapted to measure a predetermined quantity. 
     
     
       3. A data gathering unit according to claim 2 in which the meter is a utility meter. 
     
     
       4. A data gathering unit according to claim 1 which is battery-powered. 
     
     
       5. A data gathering unit according to claim 1 in which the transceiver is adapted to communicate by radio. 
     
     
       6. A data gathering unit according to claim 1 including means for extracting data transmit instructions from the signal received via its transceiver and means for transmitting data gathered, via its transceiver, in response to an instruction to do so included in the data transmit instructions. 
     
     
       7. A data gathering unit according to claim 6 in which the means for transmitting data gathered includes means for delaying the transmission of the data gathered for a predetermined period of time. 
     
     
       8. A data collection unit comprising a transceiver for the communication of information between the data collection unit and one or more remote data gathering units, means for transmitting via the transceiver a signal including power down time information and means for delaying for a period of time dependent upon the power down time information before transmitting a further signal via its transceiver. 
     
     
       9. A data collection unit according to claim 8 in which the transceiver is adapted to communicate by radio. 
     
     
       10. A data collection unit according to claim 8 in which the signal includes transmit instructions and the data collection unit includes means for extracting from a signal received via its transceiver data provided by one or more remote data gathering units in response to an instruction to do so included in the data transmit instructions. 
     
     
       11. A data collection unit according to claim 10 in which the means for extracting from the signal data provided by one or more remote data gathering units includes means for correlating that data with individual remote data gathering units in dependence upon the delay between transmission of the data transmit instructions and receipt of that data. 
     
     
       12. A telemetry system comprising one or more remote data gathering units and a central data collection unit, in which each remote data gathering unit and the central data collection unit includes a transceiver for the communication of information between the remote data gathering units and the central data collection unit, the central data collection unit comprises means for transmitting via its transceiver a signal including power down time information, each remote data gathering unit comprises means for extracting the power down time information from the signal received via its transceiver and means for subsequently interrupting the power supply to its transceiver for a period of time dependent upon the power down time information, and the central data collection unit further comprises means for delaying for a period of time dependent upon the power down time information before transmitting a further signal via its transceiver, at which time the power supply to the transceiver of each remote data gathering unit has already been resumed. 
     
     
       13. A telemetry system according to claim 12 in which the signal includes transmit instructions, each remote data gathering unit includes means for extracting the data transmit instructions from the signal received via its transceiver and means for transmitting data gathered, via its transceiver, in response to an instruction to do so included in the data transmit instructions and the central data collection unit includes means for extracting from a signal received via its transceiver the data provided by one or more remote data gathering units. 
     
     
       14. A telemetry system according to claim 13 in which the means for transmitting data gathered includes means for delaying the transmission of the data gathered for a predetermined period of time unique to the remote data gathering unit in question. 
     
     
       15. A telemetry system according to claim 14 in which the means for extracting from the signal the data provided by one or more remote data gathering units includes means for correlating that data with individual remote data gathering units in dependence upon the delay between transmission of the data transmit instructions and receipt of that data. 
     
     
       16. A telemetry system according to claim 13 in which the signal includes scramble code, each remote data gathering unit includes means for extracting the scramble code from the signal received via its transceiver and means for scrambling the data gathered prior to transmission and the central data collection unit includes means for unscrambling the signal received via its transceiver using the scramble code. 
     
     
       17. A method of collecting data from one or more remote data gathering units each including a transceiver for the communication of information, means for extracting power down time information from a signal received via its transceiver and means for subsequently interrupting the power supply to its transceiver for a period of time dependent upon the power down time information, the method comprising transmitting a signal to each remote data gathering unit including power down time information to be extracted and delaying for a period of time dependent upon the power down time information before transmitting a further signal to the remote data gathering units, at which time the power supply to the transceiver of each remote data gathering unit has already been resumed. 
     
     
       18. A method according to claim 17 in which the remote data gathering units comprise meters adapted to measure a predetermined quantity. 
     
     
       19. A method according to claim 18 in which the meters are utility meters. 
     
     
       20. A method according to claim 17 in which the remote data gathering units are battery-powered. 
     
     
       21. A method according to claim 17 in which the transceivers are adapted to communicate with one another by radio. 
     
     
       22. A method according to claim 17 in which the signal includes transmit instructions, each remote data gathering unit includes means for extracting the data transmit instructions from the signal received via its transceiver and means for transmitting data gathered, via its transceiver, in response to an instruction to do so included in the data transmit instructions and the method further includes extracting from a signal transmitted by one or more remote data gathering units the data provided by one or more of them. 
     
     
       23. A method according to claim 22 in which the means for transmitting data gathered includes means for delaying the transmission of the data gathered for a predetermined period of time unique to the remote data gathering unit in question. 
     
     
       24. A method according to claim 23, further including correlating the data provided by one or more remote data gathering units with individual remote data gathering units in dependence upon the delay between transmission of the data transmit instructions and receipt of the data. 
     
     
       25. A method according to claim 22 in which the signal includes scramble code, each remote data gathering unit includes means for extracting the scramble code from the signal received via its transceiver and means for scrambling the data gathered prior to transmission and the method includes unscrambling the signal received via its transceiver using the scramble code.